/* Macros and inline functions to swap the order of bytes in integer values.
   Copyright (C) 1997-2019 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.
   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.
   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */
#ifndef _BITS_BYTESWAP_H
#define _BITS_BYTESWAP_H 1

#include <stdint.h>

#if defined __GNUC__ && defined __GNUC_MINOR__
# define __GNUC_PREREQ(maj, min) \
        ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
# define __GNUC_PREREQ(maj, min) 0
#endif

/* Swap bytes in 16-bit value.  */
#define __bswap_constant_16(x)                                        \
  ((uint16_t) ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8)))
static __inline uint16_t
__bswap_16 (uint16_t __bsx)
{
#if __GNUC_PREREQ (4, 8)
  return __builtin_bswap16 (__bsx);
#else
  return __bswap_constant_16 (__bsx);
#endif
}
/* Swap bytes in 32-bit value.  */
#define __bswap_constant_32(x)                                        \
  ((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >> 8)        \
   | (((x) & 0x0000ff00u) << 8) | (((x) & 0x000000ffu) << 24))
static __inline uint32_t
__bswap_32 (uint32_t __bsx)
{
#if __GNUC_PREREQ (4, 3)
  return __builtin_bswap32 (__bsx);
#else
  return __bswap_constant_32 (__bsx);
#endif
}
/* Swap bytes in 64-bit value.  */
#define __bswap_constant_64(x)                        \
  ((((x) & 0xff00000000000000ull) >> 56)        \
   | (((x) & 0x00ff000000000000ull) >> 40)        \
   | (((x) & 0x0000ff0000000000ull) >> 24)        \
   | (((x) & 0x000000ff00000000ull) >> 8)        \
   | (((x) & 0x00000000ff000000ull) << 8)        \
   | (((x) & 0x0000000000ff0000ull) << 24)        \
   | (((x) & 0x000000000000ff00ull) << 40)        \
   | (((x) & 0x00000000000000ffull) << 56))
__extension__ static __inline uint64_t
__bswap_64 (uint64_t __bsx)
{
#if __GNUC_PREREQ (4, 3)
  return __builtin_bswap64 (__bsx);
#else
  return __bswap_constant_64 (__bsx);
#endif
}
#endif /* _BITS_BYTESWAP_H */
